This invention relates generally to marine mooring hardware and, specifically, to mooring fittings.
Mooring fittings are used in a variety of maritime applications. In some maritime applications, it is desirable that the mooring fitting be removable or retractable. However, some currently known removable or retractable mooring fittings require use of lifting devices powered by the marine vessel. Other currently known removable or retractable mooring fittings can present hazards to line-handling personnel.
For example, some marine vessels with a flat deck, such as barges, include bitts that are removable. Currently known removable bitts are typically attached to the deck with bolts. The bolts therefore present potentially weak load paths between the bitt and the marine vessel. Further, such removable bitts are typically heavy and require lifting devices to install and remove the bitts to and from the deck of the marine vessel. Power for such lifting devices is supplied from the marine vessel.
Some ocean-going tugboats have retractable towline guideposts. The retractable towline guideposts are typically hydraulically retracted below the deck of the tug and are hydraulically raised above deck for use. Again, hydraulic power for retracting and deploying the towline guideposts is supplied by the marine vessel.
Further, some naval submarines include retractable mooring cleats. The cleat rotates below the outer non-pressure hull to reduce surface drag. The retractable mooring cleats are bolted in a stowed or deployed position. Each half of the cleat is spring-loaded to rotate between the stowed and deployed positions. To change the position of the retractable mooring cleat between the stowed and deployed positions, the mooring cleat is unbolted and each half of the cleat is mechanically agitated to cause the spring to begin urging the cleat to its desired position. However, such operations are potentially dangerous and present hazards to line handling personnel. For example, extremities of line handling personnel may be subject to severe trauma if any of the extremities are in the vicinity of the cleat when the spring urges the cleat rapidly past an edge of the deck surface.
Thus, there is an unmet need in the art for a retractable mooring fitting that provides robust load paths between the mooring fitting and the marine vessel, does not require power from the marine vessel to retract or deploy the mooring fitting, and that minimizes potential hazards to line handling personnel.
The invention provides a retractable mooring fitting assembly that provides robust load paths between the mooring fitting and the marine vessel, does not require power from the marine vessel to retract or deploy the mooring fitting, and that retracts and deploys in a manner that minimizes potential hazards presented to line handling personnel.
According to one non-limiting embodiment of the invention, a retractable mooring fitting assembly for a marine vessel includes a mooring fitting that has a first end and a second end. A counterweight is disposed toward the second end of the mooring fitting. An axle is interposed between the counterweight and the first end, and the mooring fitting is pivotable about the axle.
According an aspect of the invention, at least a first bearing is attached to the mooring fitting. The at least first bearing is arranged to provide at least a first load path from the mooring fitting to the marine vessel. The at least first bearing is disposed intermediate the first end of the mooring fitting and the axle.
According to another aspect of the invention, a second bearing is attached to the mooring fitting. A second bearing is arranged to provide a second load path from the mooring fitting to the marine vessel. The second bearing is disposed toward the second end of the mooring fitting. If desired, the second bearing includes the counterweight.